The most common organisms responsible for se-vere CAP are Streptococcus pneunomiae, Le-gionella pneumoph, gram - negative bacilli, Haemophilus influenzae and Staphylococcus aureus.

• 重症CAP的最常见病原体有肺炎链球菌、军团菌、革兰阴性菌、流感嗜血菌和金黄色葡萄球菌等。